I. Field of the Invention
The invention relates generally to saw chains, and more particularly, to a saw chain having connecting links constructed of a nonhardened metal and tooth links constructed of extremely hard material.
II. Description of the Prior Art
Saw chains have long been known in the prior art and it is commonly known that the saw teeth of these chains rapidly become dull and must be resharpened. Generally, the saw teeth links are made of only a relatively hard metal so the blades of the saw tooth link can be ground or filed to restore a sharp cutting edge. Filing the saw chain teeth to restore their sharpness, however, is a time consuming and tedious operation.
Moreover, repeated grinding of the blades eventually wears out the saw tooth links. When the saw tooth links become overly worn, the entire saw must be replaced which in practice is very expensive to accomplish.
Another disadvantage of the previously known saw chains is that the connecting links as well as the saw tooth links are made of expensive and relatively hard metal, e.g. hardened steel, even though the connecting links undergo little wear. However, such relatively hard metal is expensive and thus increases the cost of the saw chain.